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H. C. MCDONALD. APPARATUS FOR PORGING AND SHARPENING ROCK DRILLS; 8220. No. 599,453. Patented Feb. 22, 1898.

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H. O. MCDONALD. APPARATUS FOR FORGING AND SHARPENING ROCK DRILLS, Gm.

,453. Patented Feb. 22, 1898.

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HARRY GARLYON MCDONALD, OF THE JUMPERS GOLD MINE, NEAR .TOHANNESBURG, SOUTH AFRICAN REPUBLIC.

APPARATUS FOR FORGING AND SHARPENING ROCK-=DRlLLS, 84,0.

SPECIFICATION forming part of Letters Patent No. 599,453, dated February 22, 1898.

Application filed September 22,1897. Serial No. 652,583. (No model.)

To all whom it may concern:

Be it known that I, HARRY CARLYON MC- DONALD, a subject of the Queen of Great Britain, residing near Johannesburg, in the South African Republic, have invented new and useful Improvements in Apparatus for Forging and Sharpening Rock-Drills and the Like, of which the followingis a specification.

This invention relates to improvements in apparatus for forging and sharpening rockdrills and the like, being primarily intended for producing chisel-bits, but may be employed for forging and sharpening other tools, as found desirable.

It consists, essentially, of a suitably-mounted disk provided with spring-controlled arms or hammers pivoted at one extremity on the periphery thereof, which arms or hammers as the disk is rotated beat upon a suitably-constructed anvilblock, on which the drill or tool is held for the operation of sharpening. Between the standards of the machine and carried in suitable guides an anvil block is caused to rise and fall by means of a crank or eccentric on the driving shaft upon an adjustable spring-mounted anvil-block, in which blocks are mounted, respectively, the corresponding halves of cutters and dies for cutting, rounding, and flattening the drills, when necessary, previous to sharpening the same.

The invention will be more fully described with reference to the accompanying drawings, in which Figure 1 is a side view of the machine; Fig. 2, a front view; and Fig. 3, a view showing sections of the cutters and dies for rounding and flattening, previous to sharpening, the drills.

A disk or wheel W is mounted on a suitable shaft S, carried in bearings constructed in the standards or uprights R R, motion being imparted thereto through the fast and loose pulleys P P. On the periphery of the disk V arms or hammers A A are pivoted at one end thereof, as at B B, and are controlled by adjustable involute or other springs O D and thus prevented from centrifugally flying out beyond the desired limit as the disk is revolved. Any number of these hammers may be employed, as found desirable in practice-- say three, four, five, or six, (more or less.) Slotted guides or links E E are provided as guards to prevent any lateral movement of the arms or hammers A A and also to control the same in case of emergency should the springs through any cause become inoperative.

Immediately under the disk WV is a shaper anvil F, supported on any suitable foundation or block T, upon which the centrifugal hammers A A beat as the disk is revolved. The sharpening of the drills is accomplished by holding the bits on the anvil-block F and thus bringing them under the action of the rapidly-revolving centrifugal hammers A A.

Between the standards R R of the machine, whose inner faces are planed or provided with guides, a block g g slides, motion being imparted thereto either by an eccentric or crank 011 the shaft S, having a sliding box Q, working in a cross-head q. The sliding block 9 is constructed with a dovetail, so that an upper anvil G G may be readily affixed thereto.

Immediately beneath the upper sliding block is a second block H H, mounted upon involute or other springs K K and capable of adjustment by means of the bolts J J, which on being turned either raise or depress the block, as the case may be.

L L are bolts on the standards R R, bearing upon the lower block H H for the purpose of regulating the amount of play imparted thereto by the springs K K.

The upper and lower anvil-blocks G G H 11, already described, are respectively provided with the corresponding halves of cutters a b and dies 0 d c f for the purpose of cutting, rounding, or flattening the drills previous to the operation of sharpening the same, which, as already described, is accomplished by holding the bits on the anvilF, on which the centrifugal hammers A A beat.

I wish it to be clearly understood that the machine may be used in its complete form, as herein described-win, with the anvilblooks carrying the dies for cutting, rounding, and flattening, together with the disk A, carrying the centrifugal hammers for sharpening the bits-or the last-described portion of the invention may be used by itself simply for the purpose of sharpening the bits, the rounding and flattening having been otherwise accomplished. v

Having now described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. In apparatus for forging and sharpening rock-drills or other like tools, in combination the revolving disk W with the centrifugal arms or hammers A A affixed at one end to the periphery of said disk, the slotted guardlinks E E, the adjustable controlling-springs C D to regulate the blow of the centrifugal hammers, and the fixed anvil F, substantially as described and illustrated on the accompanying drawings.

2. In apparatus for forging and sharpening rock-drills and other like tools, in combination the anvil-block H H supported by the springs K K adjustable by means of the screws J J and L L, with the rising and falling anvilblock driven by means of the crank or eccentric on the shaft of the machine, and the cutters a b, and the dies 0 d e f, substantially as described and illustrated in the accompanying drawings.

In witness whereof I have hereunto set my hand in presence of two witnesses.

HARRY CARLYON MCDONALD.

Witnesses:

WILLIAM J. ROBSON, HAROLD KISOH. 

